import java.util.Scanner;
 public class hs{
     public static void main(String[] args){
         Scanner in = new Scanner(System.in);
         int height, width;
         char status;
         height = in.nextInt();
         width = in.nextInt();
         Board board = new Board(height, width);
         status = board.getStatus();
         System.out.print(status);
     }
 }
 class Board{
    int height, width;
    public Board(int height, int width){
        this.height = height;
        this.width = width;
    }
    public char getStatus(){
        if(height<=width){
           return status(1);
        }
        else{
          return status(1.0);
        }
    }
    public char status(double rate){
        System.out.println("B");
        return 0;
     } 
     public char status(int rate){
        System.out.println("A");
        return 0;         
 
     }
 } 